The most important CAD risk factors are: smoking, high level of LDL-cholesterol and low level of HDL-cholesterol, hypertriglyceridemia, diabetes, obesity, hypertension, men sex, age over 45 in men and over 55 in women. Carl von Rokitański was the first who suggested the role of thrombosis and fibrynolisis in the development of atherosclerosis and was the author of thrombolic theory. The recently studies show that atherosclerosis is an immuno-inflamatory process. Fibrinogen as an acute phase protein is a new marker of ischemic heart disease and its role in atherosclerosis needs further investigations.